As someone who does a fair amount of SELinux professionally, I’d mostly agree with this: getting started can be daunting, so one could likely get far more value

As someone who does a fair amount of SELinux professionally, I’d mostly agree with this: getting started can be daunting, so one could likely get far more value from a short time focusing on systemd security. But if one can spare the time, SELinux can secure everything, not just systemd services. It all depends on the threat vectors one faces.